Unicom can't open green diamonds. What happened?

If the mobile phone service is unsuccessful, please consider the following reasons:

(1) Please check whether the content of the short message sent is wrong: when sending short messages, pay attention to keeping the letters in the same case;

⑵ No reply message was received due to network delay: Due to the delay in receiving information from operators in different regions, it will take some time to receive a successful corresponding message. Please be patient. You can also contact local operators (operators refer to China Mobile, China Unicom, China Telecom and China Netcom) to see if the service is successful.